CMOS積體電路應用於複彩光穩定控制之設計與實現

Design and Implementation of CMOS Integrated Circuit on Polychromatic Optical Stability Control

王嘉弘(Chia-Hung Wang)

指導教授 ： 孫台平

國立暨南國際大學/科技學院/電機工程學系/博士(2011年)

https://doi.org/10.6837/NCNU.2011.00059

摘要

一個不需要光偵測二極體以穩定輸出功率的新式LED驅動電路在本論文中提出。此驅動電路是由一個能夠補償光功率誤差的自我校準電路及一個能夠維持LED消耗電功率固定的回授控制系統所組成以取代傳統光偵測器的使用。根據一份隨溫度變化所產生的LED電氣特性與光學特性量測結果所建立而成的LED光功率特性查詢參考表扮演了補償的角色。一個由紅綠藍三色LED晶片所組成的市售全彩系統及一個由雙色燈源所混成的白光LED已依據所提出的新穎概念而實際應用。包括傳統定電流源、所提出的電功率穩定電路及具自我校準功能的光功率穩定電路會以圖解的方式進行研究並緊接著以實驗驗證其正確性。提供包括色差、發光強度、相關色溫及演色性等參數結果以作更進一步的探討。由所提出的PCB架構LED驅動電路在環境溫度變化範圍從0.5 ℃ 到85 ℃ 之間所量測出分別為紅色最大及綠色最小的幅射光通量Φ改變率為3.467 % 及2.848 %。其次，一個經由台積電0.35微米2P4M 3.3/5V 混和訊號CMOS製程所製作出來的LED積體驅動電路在本文中被提出。在5V的電源供應下，此晶片的操作頻率及輸出驅動電流設計分別為1 KHz及20 mA。由所設計的CMOS驅動IC在環境溫度變化範圍從 -40 ℃ 到85 ℃ 之間的白光LED幅射光通量Φ改變率為2.3 %。實驗結果已經驗證了一個不需要光偵測二極體的光功率穩定控制系統實際履行，應用於紅藍綠三色LED與以LED為基礎的白光燈源。

關鍵字

Light-emitting diodes ； power control ； driver circuits ； CMOS ； integrated circuit

並列摘要

This study proposes a novel light-emitting diode (LED) driver circuit that stabilizes the lighting output without a photodiode. The LED driver circuit is composed of a self-alignment circuit to compensate for the photo-power deviation and a feedback control system instead of a conventional photo-detector to maintain the electrical power of the LED. The LED characteristics, based on electrical and optical measurements that varied with temperature, were built to be a look-up reference of the generated LED photo-power, which serves as a compensator. A commercial full color LED system, which comprises red, green, and blue (RGB) LED chips, and a dichromatic white light source LED were implemented according to the novel concept. The impact of a conventional current regulator, a proposed electrical-power stabilization circuit, and a self-aligned photo-power stabilization circuit were studied graphically, followed by experimental verification. The chromaticity variation, luminous intensity, correlated color temperature (CCT), and color-rendering property are also provided for further discussion. The maximal and minimal rate of change of the radiant flux Φ driven by the proposed LED drivers in PCB configuration are 3.467 % in a red LED, and 2.848 % in green LED, respectively, over the ambient temperature range of 0.5 ℃ to 85 ℃. An LED integrated driver circuit fabricated by TSMC 0.35 μm 2P4M 3.3V⁄5V mixed signal CMOS process has been presented. The chip was designed for operating at frequency 1KHz with 5V supply voltage and 20 mA output current. The rate of change of the radiant flux Φ driven by the designed CMOS driver IC is 2.3 % in a white light LED over the ambient temperature range of -40 ℃ to 80 ℃. The experimental results verified the implementation of a lighting power stabilization control system without the use of a photodiode for RGB LEDs and white light source based on LED.

並列關鍵字

Light-emitting diodes ； power control ； driver circuits ； CMOS ； integrated circuit

參考文獻

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